Sometimes a computer is not set up to boot from the DVD/CD drive. If the LiveCD is being bypassed and the computer instead boots the OS that is installed on your hard disk drive, then there are configuration issues to review (barring any hardware failures). You either need to invoke the boot-menu during POST (Power-On Self-Test), or to change the boot sequence settings in the BIOS.

With some PCs during POST, you can press a specific key (for example, the function key F12) to enter a boot-menu where you are able to manually select the method to boot: floppy disk, CD-ROM, USB or hard disk. If no such boot-menu is featured (or can be enabled via the BIOS – as it can be sometimes), then the alternative is to change the order of boot devices in your computer’s BIOS.

To access the BIOS, press the Delete key, Insert key, or F2 during the initial power-on of the computer. (Watch the screen as the computer starts, and you should see a message that reads something along the lines of ‘Press Del to enter setup’. The key listed might be different, but the effect will be the same.) Once inside the BIOS setup, there will be a section titled “boot order” or “boot devices”. Change the list of devices accordingly and ensure that the CD-ROM or USB is listed before the hard disk drive. Once this is done, save the BIOS settings and exit the settings screen (usually by pressing the F10 key). The computer will then reboot and the LiveCD in the DVD/CD drive (or the LiveUSB) should have control of the system.